MAIZE YIELD AND SOIL PROPERTY RESPONSE TO Entada abyssinica CUTTINGS IN THE ADAMAWA LOWLANDS,

CAMEROON

By

Brian Satterlee

Submitted in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE IN FORESTRY

MICHIGAN TECHNOLOGICAL UNIVERSITY 2007

II

The thesis: “Maize Yield and Soil Property Response to Entada abyssinica

cuttings in the Adamawa Lowlands, Cameroon” is hereby approved in partial

fulfillment of the requirement for the Degree MASTER OF SCIENCE IN

FORESTRY

School of Forest Resources and Environmental Science

Signatures:

Advisor ________________________________________

Dr. Blair D. Orr

Dean __________________________________________

Dr. Margaret R. Gale

Date __________________________________________

III

TABLE OF CONTENTS

LIST OF FIGURES ......................................................................................... V

LIST OF TABLES.........................................................................................VII

ACKNOWLEDGEMENTS......................................................................... VIII

ABSTRACT.................................................................................................... IX

LIST OF ACRONYMS ................................................................................... X

CHAPTER 1 GENERAL INTRODUCTION .................................................. 1

SECTION 1 GENERAL BACKGROUND .................................................. 4

CHAPTER 2 BACKGROUND ........................................................................ 5

DESCRIPTION OF CAMEROON .................................................................. 5 ADMINISTRATIVE DIVISIONS..................................................................... 7 HISTORY ................................................................................................. 9 GOVERNMENT ....................................................................................... 10 THE PEOPLE ......................................................................................... 12 RELIGIOUS PRACTICES .......................................................................... 13 HEALTH ................................................................................................ 14 ECONOMY ............................................................................................. 15 GEOGRAPHY ......................................................................................... 18 THE ENVIRONMENTAL ISSUES ................................................................ 21 ENVIRONMENTAL POLICY ...................................................................... 22

CHAPTER 3 STUDY AREA BACKGROUND............................................ 23

THE ADAMAWA PROVINCE ..................................................................... 23 PEOPLE ................................................................................................ 24 ECONOMY ............................................................................................. 25 GEOGRAPHY ......................................................................................... 29 CLIMATE............................................................................................... 30 TREES ................................................................................................... 31 MBANG-MBOUM ................................................................................... 32

SECTION 2 RESEARCH ............................................................................ 34

CHAPTER 4 INTRODUCTION TO RESEARCH........................................ 35

CHAPTER 5 METHODS............................................................................... 37

LOCATION............................................................................................. 37 SPECIES USED ....................................................................................... 38 EXPERIMENTAL DESIGN ........................................................................ 43 FIELD PREPARATION ............................................................................. 44 CUTTINGS APPLICATIONS....................................................................... 46 SOWING MAIZE ...................................................................................... 47 STATISTICAL ANALYSIS........................................................................... 50

IV

CHAPTER 6 DATA ....................................................................................... 52

SECTION 3 IMPLICATIONS OF STUDY ............................................... 59

CHAPTER 7 RESULTS AND DISCUSSION............................................... 60

MAIZE YIELD ........................................................................................ 60 SOIL PROPERTIES.................................................................................. 62

CHAPTER 8 CONCLUSIONS AND RECOMMENDATIONS................... 71

LITERATURE CITED ................................................................................... 74

APPENDIX A................................................................................................. 78

APPENDIX B ................................................................................................. 81

APPENDIX C ................................................................................................. 83

V

LIST OF FIGURES

FIGURE 1 CAMEROON IS LOCATED IN WEST CENTRAL AFRICA ..................................... 6 FIGURE 2 YAOUNDÉ, THE CAPITAL OF CAMEROON ....................................................... 7 FIGURE 3 THE OMNISPORT AREA OF YAOUNDÉ ............................................................ 7 FIGURE 4 CAMEROON’S 10 PROVINCES......................................................................... 8 FIGURE 5 A GERMAN-BUILT PRIMARY SCHOOL............................................................. 9 FIGURE 6 HIS MAJESTY THE BELAKA (TRADITIONAL RULER) .................................... 11 FIGURE 7 CAMEROON’S DEMOGRAPHIC PROFILE. SOURCE: CIA 2006. ...................... 12 FIGURE 8 THE FETE DE RAMADAN CELEBRATION. PHOTO BY BRIAN SATTERLEE....... 13 FIGURE 9 CHILDREN COMPRISE 41.2% OF POPULATION. ............................................. 14 FIGURE 10 COTTON HARVESTED IN THE GRAND NORTH. ............................................ 15 FIGURE 11 A BUTCHER IN THE NORTH PROVINCE VILLAGE OF PITOA......................... 16 FIGURE 12 TIMBER TRANSPORTED TO DOUALA VIA TRAIN FOR EXPORT ..................... 17 FIGURE 13 CAMEROON TRADING AS A PERCENTAGE OF TOTAL EXPORTS ................... 17 FIGURE 14 GEOGRAPHIC REGIONS. ............................................................................. 19 FIGURE 15 THE SAVANNAH PLAINS NEAR GAROUA..................................................... 19 FIGURE 16 ANNUAL RAINFALL BY REGION.................................................................. 20 FIGURE 17 CHILDREN FISHING IN THE BINI RIVER, A LOGONE RIVER TRIBUTARY....... 20 FIGURE 18 SWIDDEN-FALLOW IN THE ADAMAWA....................................................... 21 FIGURE 19 NURSERIES ARE A COMMON TREE PROPAGATION METHOD ........................ 22 FIGURE 20 THE ADMINISTRATIVE DIVISIONS IN THE ADAMAWA PROVINCE. .............. 23 FIGURE 21 ETHNIC GROUPS OF THE ADAMAWA PROVINCE ......................................... 24 FIGURE 22 ZEBU CATTLE ............................................................................................ 25 FIGURE 23 A SMALL GARDEN IN THE ADAMAWA PROVINCE....................................... 26 FIGURE 24 A MBOUM MAN MAKING ROPE .................................................................. 27 FIGURE 25 LOCALLY MADE FENCING .......................................................................... 27 FIGURE 26 BRICKS SELL FOR 25 FRENCH CFA EACH. ................................................. 28 FIGURE 27 A FULBÉ MAN SUPPLEMENTING HIS INCOME AS A TAILOR ......................... 28 FIGURE 28 A DURU FAMILY PLOWING A CLIENT’S FIELD............................................. 28 FIGURE 29 BROWNISH-RED BASALT SOILS IN THE ADAMAWA..................................... 29 FIGURE 30 DRY SEASON IN THE ADAMAWA ................................................................ 30 FIGURE 31 WET SEASON IN THE ADAMAWA................................................................ 31 FIGURE 32 EUCALYPTUS, MANGO, PAPAYA TREES ...................................................... 31 FIGURE 33 SENNA SIAMEA TREE ................................................................................... 32 FIGURE 35 MARKET DAY IS EVERY WEDNESDAY IN MBANG-MBOUM........................ 33 FIGURE 36 THE VILLAGE OF LUOMO-NANGUE ............................................................ 38 FIGURE 37 ENTADA ABYSSINICA TREE DURING THE DRY SEASON .................................. 39 FIGURE 38 ENTADA ABYSSINICA BARK IS CREVICED AND FIRE RESISTANT..................... 39 FIGURE 39 ENTADA ABYSSINICA LEAVES AND FLOWERS................................................ 39 FIGURE 40 ENTADA ABYSSINICA SEED PODS CAN MEASURE UP TO 30CM ....................... 40 FIGURE 41 ENTADA ABYSSINICA SEED PODS .................................................................. 40 FIGURE 42 ENTADA ABYSSINICA SEED ENVELOPE.......................................................... 40 FIGURE 43 THERE ARE 3900 TO 4000 SEEDS PER KILOGRAM....................................... 40 FIGURE 44 OUTPLANTING A SEEDLING FROM A POLYPOT. ........................................... 41

VI

FIGURE 45 ENTADA ABYSSINICA LEAFLETS.................................................................... 42 FIGURE 47 TAKING SOIL SAMPLES WITH SOILS AUGER. ............................................... 45 FIGURE 48 SOILS AUGER AND BAGGED SOILS SAMPLES. .............................................. 45 FIGURE 49 CLEARED AND WEEDED TRIAL PLOT. ......................................................... 46 FIGURE 50 CUTTING ENTADA ABYSSINICA BRANCHES. ................................................. 46 FIGURE 51 REMOVING LARGE STEMS .......................................................................... 47 FIGURE 52 WEIGHING ENTADA ABYSSINICA CUTTINGS................................................. 47 FIGURE 53 SOWING MAIZE TWO SEEDS PER HOLE........................................................ 49 FIGURE 54 WEEDING................................................................................................... 49 FIGURE 55 WEIGHING MAIZE ...................................................................................... 49 FIGURE 56 MAIZE YIELD (METRIC TONS/HECTARE) BY TREATMENT............................ 61 FIGURE 57 MAIZE YIELD BY TREATMENT ................................................................... 61

VII

LIST OF TABLES

TABLE 1 POPULATION DENSITY OF CAMEROON’S TEN PROVINCES................................. 8 TABLE 2 SCHEDULE AND LABOR HOURS USED FOR 0.11 HECTARE RESEARCH PLOT. .... 50 TABLE 3 MAIZE YIELD IN KILOGRAMS BY TREATMENT ................................................ 52 TABLE 4 CLAY CONTENT PERCENT.............................................................................. 53 TABLE 5 FINE SILT PERCENT ....................................................................................... 53 TABLE 6 COARSE SILT PERCENT.................................................................................. 53 TABLE 7 TOTAL SILT PERCENT .................................................................................... 53 TABLE 8 FINE SAND PERCENT...................................................................................... 54 TABLE 9 COARSE SAND PERCENT ................................................................................ 54 TABLE 10 TOTAL SAND PERCENT ................................................................................ 54 TABLE 11 ORGANIC CARBON PERCENT ....................................................................... 54 TABLE 12 NITROGEN PERCENT .................................................................................... 55 TABLE 13 ORGANIC MATTER PERCENT ....................................................................... 55 TABLE 14 C:N RATIO................................................................................................... 55 TABLE 15 PH WATER................................................................................................... 55 TABLE 16 PH KCL ....................................................................................................... 56 TABLE 17 CALCIUM (CMOL/KG)................................................................................... 56 TABLE 18 MAGNESIUM (CMOL/KG).............................................................................. 56 TABLE 19 POTASSIUM (CMOL/KG)................................................................................ 56 TABLE 20 SODIUM (CMOL/KG) ..................................................................................... 57 TABLE 21 SUM OF BASES (CMOL/KG)........................................................................... 57 TABLE 22 CATION EXCHANGE CAPACITY (CMOL/KG).................................................. 57 TABLE 23 BASE SATURATION PERCENT....................................................................... 57 TABLE 24 AVAILABLE PHOSPHORUS (PPM).................................................................. 58 TABLE 25 ACIDITY (CMOL/KG) .................................................................................... 58 TABLE 26 ECEC (CMOL/KG)........................................................................................ 58 TABLE 27 NITROGEN PERCENT BY TREATMENT ........................................................... 63 TABLE 28 POTASSIUM PERCENT BY TREATMENT.......................................................... 64 TABLE 29 PHOSPHOROUS (PPM) BY TREATMENT.......................................................... 65 TABLE 30 ORGANIC MATTER PERCENT BY TREATMENT ............................................... 67 TABLE 31 ANOVA DECLARED SIGNIFICANTLY DIFFERENT AT P < 0.10....................... 69

VIII

ACKNOWLEDGEMENTS

Thanks to my mom and dad, Helen Satterlee and the late Don

Satterlee, for providing me with a strong work ethic, a desire to help others,

courage, and curiosity, and my brothers Don and Craig, my grandma the late

Violet Farris, my aunt Violet E. Farris, and my nieces Megan, Jillian, and

Chelsey for their unconditional love.

To my academic advisor, Blair Orr, I am extremely grateful for

your commitment, knowledge, honesty, advice, support, packages, stories,

breakfasts, dinners, and laughs throughout my academic career at Michigan

Tech. And for reminding me that I did not go to Cameroon to fight corruption.

You make my and others’ world a better place through your dedication to

your work.

My thanks as well to my academic committee members Pat Martin,

Robert Froese, and Jackie Grant for taking time to assist me in the thesis

writing process.

In Cameroon I would like to thank Peace Corps staff member

Clement Forkong Njiti, Martin Yemefack and the staff at IRAD, in Mbang-

Mboum His Majesty the Beleka Aboubakar Habir, Yaya Alim, Abu Amadou,

and Nana Hamadikou, and in Luomo-nangue the late Missa David for their

acceptance and guidance throughout my service. Useko jur!

Finally, many thanks to PCVs Elisabeth Kann and Robb Hill, the

Waddells, Aunt Jean and Uncle Johnny, Aunt Char and Uncle Dale, the

Masellas, Seri Robinson, Brian Henry, and my officemates in 145.

IX

ABSTRACT

Decreasing crop yields and soil fertility are a major concern of most

farmers in the Adamawa Province, Cameroon, West Central Africa. Chemical

fertilizers are generally beyond their means. Thus a need exists for an

inexpensive, natural, and sustainable chemical fertilizer alternative.

The purpose of this study was to determine the effects of Entada

abyssinica prunings through the cut-and-carry method on maize yield and soil

properties. Cuttings were applied to a 30 x 15m plot in two quantities

(1.25 kg/plot and 2.50 kg/plot) and two different application methods (mixed

or mulched). Optimal maize yield occurred when 2.50 kg prunings per plot

were mixed with the soil. Soil samples data from the plot showed significant

changes in some soil properties including increases in potassium, organic

matter, organic carbon, and soil pH.

For the smallholder farmer without the means to acquire chemical

fertilizer, Entada abyssinica cuttings are an effective alternative. Entada

abyssinica is indigenous to Africa and is valued for its multiple uses. This

study indicates that positive results can be experienced in the same cropping

season, which can lead to increased adoption rates and less dependence on

inorganic fertilizers.

X

LIST OF ACRONYMS

CAR Central African Republic CDU Cameroon Democratic Union CRTV Cameroon Radio Television GIC Groupe d’Initiative Communitaire HIPC Heavily Indebted Poor Countries Initiative IITA International Institute for Tropical Agriculture IRAD Institute of Agricultural Research for Development MINAGRI Ministry of Agriculture MINEF Ministry of Environment and Forests MINREST Ministry of Technical Research NGO Non Governmental Organization NUDP National Union for Democracy and Progress PCV Peace Corps Volunteer SDF Social Democratic Front UN United Nations UPC Union of the People of Cameroon USAID United States Agency for International Development ZEW Zonal Extension Worker

1

CHAPTER 1 GENERAL INTRODUCTION

As an Agroforestry Extension Agent with Peace Corps Cameroon I

was posted in the village of Mbang-Mboum, a small canton in the Adamawa

lowlands. My primary responsibilities were to teach motivated farmers the

techniques of agroforestry and to identify farmer leaders who would adopt a

technique or two in their farms and pass on this knowledge to others.

Armed with a year of stateside coursework and three months of in-

country training, I began visiting farms in my work area and asking farmers

how they could improve their land. “Buy us fertilizer so we’ll have more

maize” was the common demand.

The agroforestry technique green manuring could naturally and

sustainably improve soil fertility and would be a perfect substitute for man-

made inputs. How could a city boy from Detroit convince subsistence farmers

in sub- Saharan Africa to adopt this technique?

Patience. Building trust. Hard work. Tangible results. Luck.

Combining my primary assignment and my research seemed like a

smart approach. After campaigning for some land, I created a demonstration

plot in the center of my village that exhibited green manure’s effects on maize

yield and was also given a larger plot in another village to conduct field trials

for my research on green manure. Thus, I was able to assist farmers and

accomplish my research needs simultaneously.

2

My objective for this study was to examine green manure’s effect

on maize yield and soil properties utilizing the cut and carry method and to

provide farmers in Mbang-Mboum and the surrounding villages with a

chemical fertilizer alternative. I hypothesized that both maize yield and soil

properties would show significant changes.

Chapter 2 provides background information about the country of

Cameroon and concludes with a summary of environmental issues facing the

country and policies to combat them. The Adamawa Province where the study

took place is discussed in Chapter 3 including the different ethnic groups that

reside in the province and their occupations. Additionally, the village of

Mbang-Mboum is described in more detail.

In Chapter 4 the motivation for my research is explained,

particularly its importance to subsistence farmers in the Adamawa. I outline

the methodology for my field trials in Chapter 5: location, tree species used,

experimental design, and field work, concluding with a description of the

statistical analysis utilized in the trials and data collected.

Chapter 6 presents the data collected during this experiment

including maize yield, macronutrient, and micronutrient soil sample test

results. I continue in chapter 7 with the results and discussion section. I begin

with maize yield and continue with specific soil properties. Throughout this

chapter, comparisons of my results to other studies are made. Chapter 8 covers

conclusions drawn from this field trial. I examine the results of this study as

they relate to present day conditions in the Adamawa lowlands and conclude

3

with suggestions to increase agroforestry adoption rates in the province.

4

SECTION 1

GENERAL BACKGROUND

5

CHAPTER 2 BACKGROUND

The Republic of Cameroon has been in the global spotlight on

numerous occasions over the past several decades. In 1987, Lake Nyos in the

Southwest Province released poisonous gases killing approximately 2000

villagers as they slept. The National Soccer team’s 1990 performance in the

World Cup competition brought praise to the Indomitable Lions throughout

the international soccer community. 1999 brought recognition as the world’s

most corrupt nation (Transparency International, 1999) and also in 2003 with

the completion of a controversial underground oil pipeline from Chad to the

city of Kribi on the Atlantic Ocean. In 2006, scientists traced the origin of the

HIV virus to chimpanzees also in the Southwest Province and the country

reached the World Bank’s Heavily Indebted Poor Countries (HIPC) initiative

completion point (World Bank, 2006). Because of its political stability,

however, Cameroon receives little attention when compared to other Central

African countries. Much is yet to be explored.

Description of Cameroon

Cameroon is a triangle-shaped country stretching from the Gulf of

Guinea in the south to Lake Chad (Figures 1 and 2) in the north. With a land

area of 475,400 km² (World Bank, 2006), it ranks as the world’s 53rd largest

country, approximately the size of the U.S. state of California

(State Department, 2006). Frontier countries include Nigeria to the west,

6

Equatorial Guinea and Gabon to the south, the Democratic Republic of Congo

and the Central African Republic to the east, and Chad to the north. The

capital city Yaoundé lies in the Center Province (Figure 3).

Figure 1 Cameroon is located in West Central Africa. Source: http://www.lexnet.be/africa.jpg

7

Figure 2 Yaoundé, the capital of Cameroon. Source: https://www.cia.gov/cia/publications/factbook/geos/cm/html.

Figure 3 The Omnisport area of Yaoundé. Photo by Brian Satterlee.

Administrative Divisions

The country is composed of ten provinces: the Adamawa Province,

Center Province, East Province, Extreme North Province, Littoral Province,

8

North Province, Northwest Province, West Province, South Province, and

Southwest Province (Figure 4). The East Province is the largest, followed by

the Center, the North, and the Adamawa while the West is the most densely

populated, the East the least (Table 1). Cameroon is divided into 58 divisions

and further subdivided into subdivisions and districts.

Figure 4 Cameroon’s 10 Provinces

Table 1 Population density of Cameroon’s ten provinces. Source: Yebit, 2004

PROVINCE POPULATION AREA DENSITY (Millions) (km²) (Population/ km²) Adamawa 0.7 62,000 11.3

Center 2.3 69,000 33.3 East 0.7 109,000 6.4 Extreme North 2.5 34,360 72.8

Littoral 1.9 21,500 88.4 North 1.1 68,000 16.2 Northwest 1.7 17,400 97.7 South 0.5 47,190 10.6 Southwest 1.2 34,720 34.6 West 1.8 13,890 129.6

9

History

Portuguese sailors landed on the coast near present day Douala in

1472 and were amazed at the number of prawns and crayfish in the Wouri

River and named it Rio dos Camarões, the phrase which gives Cameroon its

name (Peace Corps, 2002). Centuries of trade with Europeans and contact

with Christian missionaries along the coast followed and moved inland in the

late 1800s when malaria was suppressed through the use of quinine

(State Department, 2006).

Cameroon became the German colony of Kamerun in 1884

(State Department, 2006). Infrastructure improvement projects including

roads and railways were undertaken as well as the construction of hospitals

and schools (Figure 5). After World War I the country was divided between

Britain and France (World Bank, 2006); France received a larger share of the

country. Its influence is still prevalent today as evidenced by the use of the

French education system, language, and continued military advising (Wolf,

2001).

Figure 5 A German-built primary school. Photo by Brian Satterlee.

10

In December 1958 the region was given self-government and in

1960 complete independence and United Nations (UN) membership

(World Bank, 2006). The British southern and French portions were combined

in 1961. The northern British section joined Nigeria. Thus the Federal

Republic of Cameroon was born with Ahmadou Ahidjo as the country’s first

president (World Bank, 2006).

Ahidjo was a French-educated Fulani from the North. In 1966 he

banned all political parties but the one with which he was affiliated and

suppressed the Union of the Peoples of Cameroon (UPC) party rebellion in the

late 1960s. He resigned in 1982 (State Department, 2006). His Prime Minister,

Paul Biya, a Bulu-Beti from the South, succeeded Ahidjo, survived a 1984

coup d’etat, and continues to serve as president today (State Department,

2006).

Government

Based on the French civil law system, Cameroon has a powerful

central government that is controlled by the President (State Department,

2006). He has the authority to appoint and dismiss cabinet members as well as

most government officials. He has complete veto power and control over the

state owned firms’ finances without consulting the country’s National

Assembly, a 180-member branch that adopts laws by majority vote. He heads

the Supreme Court, consisting of the president, the minister of justice, and the

judicial advisers. A law’s constitutionality can only be reviewed when he

11

requests it (State Department, 2006). Local government functions such as

property and domestic disputes are handled by traditional rulers and councils

(Figure 6).

Figure 6 His Majesty the Belaka (Traditional Ruler). Photo by Brian Satterlee.

Amendments to the country’s 1972 constitution were made in

1995 resulting in a revised constitution in 1996 (State Department, 2006).

Changes included the creation of a 100-member Senate, regional tribunals,

and limiting the president’s term to seven years with one additional term. The

Social Democratic Front (SDF), the National Union for Democracy and

Progress (NUDP), and the Cameroon Democratic Union (CDU) parties

oppose the People’s Democratic movement which has been in power since

independence in 1960 (State Department, 2006).

With such a powerful central government it follows that the

media is heavily censored. The state owned company Cameroon Radio

Television (CRTV) monopolizes the airwaves although legislation against

12

such a practice passed in 2000 (State Department, 2006). The government has

shut down newspapers, failed to issue broadcast licenses to private networks,

and arrested journalists. Human rights activists remain concerned over reports

of the Government’s beatings, illegal searches, and unwarranted arrests

(State Department, 2006).

The People

English and French are the two official languages, although

there are over 200 others spoken within the country including Fulfuldé,

pidgin, and Ewondo. Fulfuldé is said to be spoken by approximately

10,000,000 people throughout West and Central Africa (Peace Corps, 2002).

There are over 250 ethnic groups of Bantu, Sudanese, and Arabic origins: the

western highlanders, the coastal tropical forest peoples, the southern tropical

forest peoples, the Islamic peoples of the Sahel and central highlands, and the

Kirdi (non-Islamic) of the northern desert and central highlands (State

Department, 2006). The Bamileke, Bamoun, and Tikar groups in the Western

Highlands make up the majority of Cameroon’s population (Figure 7).

Non-Islamic (Sahel)18%

Islamic (Sahel)14%

Southern Forest18%

Western Highlanders

38%

Coastal Forest12%

Figure 7 Cameroon’s Demographic Profile. Source: CIA 2006.

13

Religious Practices

Christianity and indigenous beliefs account for 75% of the

population’s faith (State Department, 2006). Christians generally live in the

southern provinces while animism is practiced in smaller, remote villages

throughout the country. Muslims dominate the Grand North (Adamawa,

North, and Extreme North provinces) and regularly participate in the activities

the religion dictates like the Fete de Ramadan (Figure 8). Regardless of the

belief system, sorcery and witchcraft are often used to explain events such as

poor harvests, drought, and even death (Peace Corps, 2002). Allah’s or God’s

will is also used to explain floods that wipe out roads and bridges rather than

poor engineering (Beets, 1990).

Figure 8 The Fete de Ramadan celebration. Photo by Brian Satterlee.

14

Health

There is a high risk of major infectious diseases throughout the

country. Food or waterborne diseases include bacterial diarrhea, hepatitis A,

and typhoid fever. Malaria and yellow fever are high risks as is a water

contact disease known as schistosomiasis. Meningococcal meningitis can

invade respiratory systems and lead to early mortality (CIA, 2006). For

example, male life expectancy is only 50.98 years, 51.34 years for females,

and 51.16 years for the total population (CIA, 2006). Children up to fourteen

years (Figure 9) represent 41.2% of the population and are most at risk

because of their low social status. People living with HIV/AIDS were

estimated at 560,000 with an annual mortality rate of approximately 10%.

Traditional remedies composed of roots, leaves, and flowers are often

substituted for more modern treatments (CIA, 2006).

Figure 9 Children comprise 41.2% of population. Photo by Brian Satterlee.

15

Economy

Cameroon is often referred to as Africa’s bread basket because it

is one of the few net food exporters in Africa and agriculture is the driving

force behind the economy (Peace Corps, 2002). Approximately 70% of the

population is involved in agriculture and these activities account for more than

44% of Gross Domestic Product (GDP) (CIA, 2006). Main cash crops are

coffee, cocoa, cotton, oilseed, and rubber (Figure 10). Other agricultural

products include bananas, sugar cane, corn, and other grains such as wheat

and millet.

Figure 10 Cotton harvested in the Grand North. Photo by Brian Satterlee.

In addition to farming and agriculture, Cameroon’s labor force is

also involved in petroleum production, food processing, aluminum

production, and light consumer goods (CIA, 2006). These activities account

for 55% of GDP and employ more than 2 million workers (CIA, 2006).

Tourists attracted to the country’s seven national parks and West Africa’s

16

tallest peak, Mt. Cameroon, provide a source of additional income for guides,

porters, drivers, and hotel workers.

Over 30% of Cameroon’s 6.86 million labor force is

unemployed and 48% of the population is living below the poverty line

(CIA, 2006). Many set up craft shops in large cities and target tourist dollars.

Others manage large herds of cattle and sell one or two weekly to raise money

for farm input costs such as labor and fertilizer (Figure 11).

Figure 11 A Butcher in the North Province village of Pitoa. Photo by Brian Satterlee.

Cameroon’s exports are valued at $US 3.236 billion (CIA, 2006)

and include crude oil, petroleum products, and lumber (Figure 12). Major

trading partners include Belgium, France, Italy, the Netherlands, and Spain

(State Department, 2006). The country imports electrical equipment, fuel,

food, machinery, and transport equipment totaling $US 2.514 billion

(CIA, 2006), approximately a third of which comes from France and Nigeria

(Figure 13).

17

Figure 12 Timber transported to Douala via train for export. Photo by Brian Satterlee.

0%

5%

10%

15%

20%

25%

0%

5%

10%

15%

20%

25%

France Nigeria BelgiumChina US Thailand

Figure 13 Cameroon trading as a percentage of Total Exports. Source: CIA 2006

18

Geography

Its distinct climatic regions and five geographic zones

(Figure 14) have led people to refer to Cameroon as “Africa in Miniature” or

the “Microcosm of Africa” (Nyamnjoh, 1999). The densely forested, hot and

humid coastal plain is home to Douala, Cameroon’s largest city and financial

capital. It receives the most rainfall in the country. Lower in humidity and

cooler, the low southern plateau has an average elevation of 450 to 600m and

is primarily tropical rainforest (Onguene, 2001). Both regions are home to 22

primate species and notable tree types including oil palms, mahogany, teak,

and ebony. The Western Highlands, with fertile volcanic soils, contains hills,

plateaus, and mountains that extend over 1000km north. The Adamawa

Highlands are a combination of grasslands, forests, and mountains that

separate the north and south. Elevations are approximately 1000m. Unlike the

regions to the south, the Adamawa Highlands have only two seasons; the dry

season and the wet, both lasting approximately six months. Finally the

savanna plain (Figure 15) extends northward to the border between Nigeria

and Chad. Rainfall varies between 400 and 750mm annually with

temperatures up to 45ºC (Figure 16). Desertification is a major environmental

concern in this region.

19

Figure 14 Geographic Regions.

Figure 15 The savannah plains near Garoua. Photo by Brian Satterlee.

20

Figure 16 Annual rainfall by region. (Adapted from Yebit, 2004)

Four major rivers in the south flow directly into the Gulf of Guinea.

Two others, the Dja and the Kadeï, drain into the Congo River. In the Grand

North (Adamawa, North, and Extreme North Provinces), the Benoué flows

into the Niger and the Logone (Figure 17) into Lake Chad.

Figure 17 Children fishing in the Bini River, a Logone river tributary. Photo by Brian Satterlee.

21

The Environmental Issues

During the mid-1980s the world market for Cameroon’s major

exports (coffee and cocoa) crashed, forcing more people into the agricultural

sector (Yebit, 2004). This resulted in a per capita decrease in the amount of

arable land available for cultivation and an increase in deforestation in order

to satisfy the demand for such land. Forested area decreased rapidly as new

plots were cleared. For example, between 1990 and 1995 total forested area

declined 3.3% (Yebit, 2004). Over 2200 km² was lost annually between 2000

and 2005 (World Bank, 2006).

Naturally the exploitation of the forested areas leads to other

concerns. Wildlife habitat for Cameroon’s diverse animal species was lost.

Surface runoff caused soil erosion and the loss of valuable nutrients critical to

sustain acceptable crop yields. Springs dried up. The fallow periods in

swidden-fallow cultivation systems (Figure 18) were eliminated (Yebit, 2004).

Tree species used for fuel wood, medicinal, and ceremonial purposes

disappeared. As population increased people left the areas in search of new

lands and resources which became less abundant. Farmer-grazer conflicts

became commonplace. The cycle continues today.

Figure 18 Swidden-fallow in the Adamawa. Photo by Brian Satterlee

22

Environmental Policy

The government of Cameroon created the Ministry of

Environment and Forests (MINEF), the Ministry of Agriculture (MINAGRI),

and the Ministry of Technical Research (MINREST) to combat the country’s

environmental concerns (Yebit, 2004). MINREF oversees forest management,

timber harvesting, propagation, and agroforestry (Figure 19). MINAGRI

utilizes Zonal Extension Workers (ZEWs) to work with farmers in promoting

sustainable farming techniques. MINREST collaborates with international

organizations such as IRAD (Institute of Agricultural Research for

Development), IITA (International Institute for Tropical Agriculture), and

ICRAF (International Center for Research in Agroforestry). These research

institutes conduct field trials and make suggestions based on their findings.

Figure 19 Nurseries are a common tree propagation method. Photo by Brian Satterlee.

23

CHAPTER 3 STUDY AREA BACKGROUND

The Adamawa Province

The Adamawa Province comprises approximately 64,000 km² and

is the gateway to the Grand North. It is the third largest province yet ranks 8th

in population density at 11.3 persons /km². It is often dubbed the Forgotten

Province because of its lack of development. It borders the Center and East

Provinces to the south, Nigeria to the east, the Central African Republic to the

west, the Northwest and West Provinces to the southwest, and the North

Province to the north. There are five administrative divisions or departments;

Djérem, Faro-et-Déo, Mayo-Banyo, Mbéré, and Vina (Figure 20). The capital

city is Ngaoundéré. (Yebit, 2004).

Figure 20 The Administrative Divisions in the Adamawa Province.

24

People

There are over ten ethnic groups that reside in the Adamawa

(Figure 21). The majority are the Fulbé, Mboum, Duru, Gbaya, and Haussa

(Peace Corps, 2002). The Fulbé are proud and religious Muslims, often

wealthier than other groups because of their large cattle herds. The Mboum

are reported to be the first settlers in the area (Hino, 1984) and farming was

their principal occupation. The Duru migrated into the Adamawa between the

late 1600 and 1700s in search of farmland and intermarried with the Mboum.

Originating from Central Africa, the Gbaya came to the Adamawa in the early

1700s and were generally subordinate to the Mboum. Haussa arrived at the

same time as the Gbaya from West Africa and engaged in trading cattle and

kola nuts.

Figure 21 Ethnic groups of the Adamawa Province. Adapted from Peace Corps, 2002.

25

The Fulbé Islamized most of the Adamawa shortly after their

arrival in the mid-19th century. The Mboum, Duru, and Gbaya were given the

choice of converting or being enslaved (Hino, 1984). Few resisted. Today the

groups peacefully co-exist and have mutually benefited from knowledge

exchange. For example, the Mboum educated the Fulbé about maize

cultivation. The Fulbé in turn shared their animal husbandry knowledge.

Economy

Cattle production is the Adamawa’s major economic activity due

to the province’s low population density and consistent and thick grass cover.

Most of the animals are humpbacked zebu (Bos indicus) owned by the Fulbé

(Figure 22). The herds are often transported along the western third of the

province and along the Chadian border to the big markets in Yaoundé,

Douala, Gabon, and the Congo (Yebit, 2004).

.

Figure 22 Zebu cattle. Photo by Brian Satterlee.

26

Like the majority of Cameroon people, farming is the principal

activity in the Adamawa as well, generally an upland cereal based system

which is the prevalent system in semi-arid climates (Beets, 1990).

Approximately 25 years ago, millet and manioc dominated small fields

(Yebit, 2004). Today maize (Zea mays) cultivation is the principal farm crop

on bigger plots, sometimes more than five hectares in size. Smaller gardens of

sugar cane (Saccharum officinarum), tomatoes (Lycopersicon lycopersicum),

snap beans (Phaseolus vulgaris), pepper (Capsicum annum), pineapple

(Ananas comosus), and groundnuts [peanuts] (Arachis hypogaea) supplement

income and add nutrients to people’s diets (Figure 23).

Figure 23 A small garden in the Adamawa Province. Photo by Brian Satterlee.

Additional sources of income include using the area’s natural

resources to construct and sell rope, fencing, and bricks as well as self-

employment as tailors and operating plows (Figures 24-28).

27

Figure 24 A Mboum man making rope. Photo by Brian Satterlee.

Figure 25 Locally made fencing. Photo by Brian Satterlee

28

Figure 26 Bricks sell for 25 French CFA each. Photo by Brian Satterlee.

Figure 27 A Fulbé man supplementing his income as a tailor. Photo by Brian Satterlee.

Figure 28 A Duru family plowing a client’s field. Photo by Brian Satterlee.

29

Geography

The Adamawa is perhaps Cameroon’s most diverse area

(Yebit, 2004). Mountainous areas like the Gotel and Mambila Mountains

border Nigeria and to the east the Tchabal Mbabo peak at 2460 m. The

Adamawa Plateau then begins to the north at about 6 degrees latitude and

continues to about 8 degrees. It stretches east to the Central African Republic

(CAR). Altitudes average 1000 to 2000 m, but dip to a low of 500 m in the

Djérem and Mbéré valleys.

Soils are generally brown or brownish-red ferralitic developed

from ancient basalts (Figure 29), the result of the annual shift between dry and

wet conditions and soil wash from the mountains (Mapongmetsem, 2005).

Iron and aluminum content is high causing oxidized hardpans. Many of the

province’s mountains contain a mixture of several soil types.

Figure 29 Brownish-red basalt soils in the Adamawa. Photo by Brian Satterlee.

30

The Adamawa is often referred to as Cameroon’s water tower

because many of the country’s rivers begin in the province (Yebit, 2004).

They all fall into a tropical regime, a period of high water from May to

September (rainy season) and a period of low water or possibly complete

dryness from October to April. They drain into three basins: the Niger River,

Lake Chad, and the Atlantic Ocean (Yebit, 2004).

Climate

The climate of the Adamawa Plateau is classified as tropical of

the Sudano-Guinean type (Mapongmetsem, 2005). There are two seasons. The

dry season or la saison seche (Figure 30) begins in November and lasts until

April. Nightly temperatures from November to January are around 15°C. In

March and April afternoon temperatures climb to over 38°C . The wet season

(la saison de pluie) starts in April. Rainfall averages approximately 1300 mm

annually. Heaviest precipitation occurs in the months of May, June, and

August. The vista changes from light brown to a sea of green as vegetation

springs back to life (Figure 31).

Figure 30 Dry season in the Adamawa. Photo by Brian Satterlee.

31

Figure 31 Wet season in the Adamawa. Photo by Brian Satterlee.

Trees

Most of the Adamawa is sparsely wooded savanna with heavily

wooded areas bordering the many rivers and streams (Yebit, 2004). Notable

tree species include Eucalyptus cameldulensis and Ficus spp as well as fruit

trees such as mango (Mangifera indica), papaya (Carica papaya), avocado

(Persea americana), banana (Banana spp), grapefruit (Citrus paradisi), and

oDifference (Citrus sinensis) (Figure 32). Agroforestry species (Figure 33)

include Caesalpinia decapitala, Senna siamea, and Entada abyssinica

(Mapongmetsem, 2005).

Figure 32 Eucalyptus, mango, papaya trees. Photo by Brian Satterlee.

32

Figure 33 Senna siamea tree. Photo by Brian Satterlee.

Mbang-Mboum

Mbang-Mboum is a Muslim dominated canton located at

latitude 7°30’ N and longitude 13°50’ E (Figure 34). The name is derived

from the neighboring mountains (Mbang) and the area’s first settlers (Mboum)

(Ahmadou, 2004). Population is approximately 900 (Ahmadou, 2004). There

is no electricity or running water and limited health care at the village health

center. The principal activity is maize cultivation, using a mid-elevation

cultivar, SHABA (Christensen, 1994). Market day is every Wednesday when

villagers sell their grains and other produce from homegardens (Figure 35).

Methods to increase yields and income are a top priority.

Figure 34 The village of Mbang-Mboum. Photo by Brian Satterlee.

33

Figure 35 Market day is every Wednesday in Mbang-Mboum. Photo by Brian Satterlee.

Mbang-Mboum and other villages throughout the Adamawa suffer

from a lack of infrastructure, economic development, and social programs in

comparison to the northern and southern provinces. Farming is generally the

only available occupation. Access to markets is difficult due to poor roads.

Life skill programs including financial management, time management, and

family planning are uncommon. The government eliminated its 65% subsidy

of fertilizer costs; crop yields are dwindling. People here feel lost, forgotten,

and desperate.

34

SECTION 2

RESEARCH

35

CHAPTER 4 INTRODUCTION TO RESEARCH

Adamawa residents have sufficient water resources, a favorable

climate, and low population density. The various ethnic groups boast of

peaceful co-existence for centuries. Vegetation used for firewood, to construct

houses, fencing, and rope is adequate. Desertification is not yet a major

concern. However, inhabitants of the Forgotten Province have not experienced

development programs enjoyed in other areas of Cameroon.

The government once subsidized the cost of fertilizers, so farmers

enjoyed higher yields, increased income, and ample food supply. Today those

subsidies have been eliminated. Farmer morale suffers. Thus a need exists for

an inexpensive, natural, and sustainable chemical fertilizer alternative in the

Adamawa. Using green manure is an excellent choice (Beets, 1990).

Adoption of a new technology such as green manure is a difficult

and slow process, particularly when new methods originate from a

development worker. Farmers have been practicing the same techniques for

generations and are hesitant to change them. A whole seasons’ crop could be

lost by a poorly executed technical introduction. Often it is simply not worth

the risk.

The challenge was to convince farmers that green manure was a

viable chemical fertilizer alternative. Telling people is rarely as effective as

teaching them. The combination of hands on education and tangible results

was the key. Thus, the purpose of this field trial was to determine how the

36

leaves of Entada abyssinica used as green manure would improve maize yield

and soil properties. Perhaps favorable results could convince farmers of its

value.

37

CHAPTER 5 METHODS

Entada abyssinica cuttings were applied as a mulch (spread evenly

on the surface) or mixed with the soil using a hoe in two different quantities.

Maize was sown and harvested at physiological maturity. Soils samples were

taken prior to applying the cuttings and again five weeks before harvest. Yield

data was obtained after harvest. Characteristics of the trial plot will be

described first in this section followed by information about Entada

abyssinica. Next, the experimental design will be explained preceding a

description of the field work used for the trial. Finally, this section will

conclude with a description of the statistical analysis methodology.

Location

The research plot was located in a two-hectare farm in the

village of Luomo-nangue. Located approximately 8 km northwest of Mbang-

Mboum, Luomo-nangue bordered the recently completed Ngaoundéré-

Touboro highway (Figure 36). The farm was protected by barbed wire and

wood posts on three sides. The fourth side bordered a stream and was left

unprotected. Crop damage from free roaming cattle and monkeys from the

surrounding mountains had been experienced in the past. The plot was planted

in maize in July 2005 and laid fallow after harvest. Trials began in July 2006.

38

Figure 36 The village of Luomo-nangue. Photo by Brian Satterlee.

Species used

Entada abyssinica (Steud.ex A.) is a savannah tree that grows to

12m (FAO, 2006). Its branches are low to the ground. The crown is narrow

and open (Figure 37). The bark has crevices and is gray in color (Figure 38).

Leaves are alternate, compound, and bipinnate measuring up to 45cm in

length with up to 20 pairs of leaflets. Flowers are white to creme colored, 7 to

15cm long (Figure 39). Pods can grow 15 to 30cm in length and contain 12 to

15 seeds (Figure 40 and Figure 41). The seeds are encased in a two-winged

capsule (Figure 42). There are 3900 to 4000 seeds per kilogram (Figure 43),

(FAO, 2006).

39

Figure 37 Entada abyssinica tree during the dry season. Photo by Brian Satterlee.

Figure 38 Entada abyssinica bark is creviced and fire resistant. Photo by Brian Satterlee.

Figure 39 Entada abyssinica leaves and flowers. Photo by Brian Satterlee.

40

Figure 40 Entada abyssinica seed pods can measure up to 30cm. Photo by

Brian Satterlee.

Figure 41 Entada abyssinica seed pods. Photo by Brian Satterlee.

Figure 42 Entada abyssinica seed envelope. Photo by Brian Satterlee.

Figure 43 There are 3900 to 4000 seeds per kilogram. Photo by Brian Satterlee.

41

Entada abyssinica is native to Africa and can be found

throughout the Sudanian and Guinean Savannas from Ivory Coast in West

Africa to Somalia in East Africa and as far south as Mozambique

(World Agroforestry Center, 2006). It is a member of the Fabaceae family and

the Mimosaceae subfamily. Members of the family are important sources of

animal feed or green manure (FAO, 2006). It fixes atmospheric nitrogen.

Growing at elevations between 60 and 2300m and requiring rainfall from 500

to 1300mm, it tolerates soils ranging from loam to clay loams and at times

friable clay over laterite (FAO, 2006). It is shade intolerant (FAO, 2006).

Entada abyssinica can be propagated through seedlings, direct

sowing, and reproduce naturally by root suckers, seed, and coppicing. Seed

treatment involves placing the seeds in hot water overnight then placing them

in polypots. Germination rates vary between 70 and 90%. Seedlings are

outplanted after 3 to 4 months (Figure 44), (FAO, 2006).

Figure 44 Outplanting a seedling from a polypot. Photo by Brian Satterlee.

42

Indigenous tree species like Entada abyssinica have often been

used throughout the tropics to satisfy peoples’ basic needs. Rural households

depend on trees for firewood, fruit, and traditional medicines as well as to

provide shade and fodder for livestock (Nair, 1998). Indigenous tree species

are found to be more resistant to pests and diseases than non-native species.

Exotic species, on the other hand, are prone to pest and disease problems and

can also become invasive.

Entada abyssinica is used throughout Africa as medicine, mulch,

and in rainmaking ceremonies (FAO, 2006). The root bark is boiled and then

removed and the remaining liquid is consumed as a traditional remedy for

chronic cough, headache, and stomach pains (Rukangira, 2004). In the Nkol-

Nguele village in the Center Province of Cameroon, the fruit is used as a

scraping stick to smooth calabash walls during pottery making (Swartz, 1989).

Found in the Adamawa Province of Cameroon (Mapongmetsem et al, 2005),

it is commonly known as pade waandu or monkey sandals because of the

shape of its leaflets (Figure 45).

Figure 45 Entada abyssinica leaflets. Photo by Brian Satterlee

43

Because Entada abyssinica is abundant and well recognized in the

Adamawa it can be rapidly incorporated in the farm system. Green manuring

involves adding leafy biomass to soils in order to improve soil fertility

(Thurston, 1997). Valuable nutrients such as nitrogen, phosphorous, and

potassium are released into the soil as the biomass decomposes. The biomass

also holds water that assists in transporting nutrients to the roots of associated

crops, like maize. Green manure also suppresses weed growth, improves soil

structure, and helps in the prevention of soil erosion.

Experimental Design

A complete-block design of five blocks with five treatments was

laid out sequentially on a plot measuring 30 x 15 m (Figure 46). Each subplot

measured 6 x 3 m. The following specifications were arranged in each block:

1. Treatment A was the control. No cuttings were applied.

2. Treatment B used 1.25 kg cuttings and was mixed with the soil using a

hoe (1.25/Mix).

3. Treatment C used 1.25 kg cuttings and was mulched on the surface

(1.25/Mulch).

4. Treatment D used 2.50 kg cuttings and was mixed with the soil using a

hoe (2.50/Mix).

5. Treatment E used 2.50 kg cuttings and was mulched on the surface

(2.50/Mulch).

44

The rationale for the selected quantity of cuttings follows similar

experiments in Africa. Kang et al (1981a) used nitrogen rate (N-rate)

equivalences of 30 and 60 kilograms per hectare (30 and 60 kg N/ha) with

Leucaena leucocephala prunings as green manure for maize. Similarly,

Mugendi et al (1999a) used 60kg N/ha equivalencies of Calliandra

calothyrsus and Leucaena leucocephala and monitored soil-fertility changes

and maize yield. Entada abyssinica nitrogen equivalencies at 1.25 kg and

2.50 kg are 20 and 40 kg N/ha respectively.

Figure 46 Complete block design of experimental layout.

Field Preparation

Subplots were delineated with nylon cord and wooden stakes.

Five soil sample locations were randomly selected in each subplot and taken

with a soil auger at 20cm depths (Figure 47). Soil samples were bagged,

Block

1 A B D E C

2 D C A B E

3 B D E C A

4 A B E C D

5 D C B A E

45

labeled (Figure 48), and taken to IRAD Nkolbisson office in Yaoundé.

Analysis (method in parentheses) included particle size distribution

(Pipette method), organic carbon (Black and Walkey method), total nitrogen

(mineralization with a Tecator), organic matter (Walkey and Black), C:N

ratio, available phosphorus (Bray II), exchangeable cations (Ammonium

Acetate N at pH 7), and cation exchange capacity (determination by KCl

according to BASCOM at pH 8.1), (Yemefack, 2006). Next the plot was

cleared and weeded (Figure 49).

Figure 47 Taking soil samples with soils auger. Photo by Brian Satterlee.

Figure 48 Soils auger and bagged soils samples. Photo by Brian Satterlee.

46

Figure 49 Cleared and weeded trial plot. Photo by Brian Satterlee. Cuttings applications

Small branches of Entada abyssinica trees bordering the farm

were cut with a machete (Figure 50). Generally this species is not

intercropped with field crops because of its shallow root system and

competition for water, light, and nutrients. Stems larger than 10mm were

removed (Figure 51) and the remaining smaller stems and leaves were

allowed to air dry for three days. Cutting and removing stems required 8.5

labor hours. The cuttings were then weighed (Figure 52) and either mixed

with the soil using a hoe or applied evenly on the top of the soil as a mulch to

the subplots. This process took 11 labor hours.

Figure 50 Cutting Entada abyssinica branches. Photo by Brian Satterlee.

47

Figure 51 Removing large stems. Photo by Brian Satterlee.

Figure 52 Weighing Entada abyssinica cuttings. Photo by Brian Satterlee.

Sowing maize

Sowing the maize cultivar SHABA followed traditional

practices using local tools. SHABA is a mid-elevation variety that was

developed in 1988 by a USAID project in the Shaba Province, Democratic

48

Republic of the Congo (formerly Zaire). It was introduced and adopted in the

Adamawa Province of Cameroon shortly afterwards (Christensen, 1994).

Spacing distance also followed traditional planting methods. Maize

was sown at a spacing of 80 cm x 25 cm. The intra-row spacing (25 cm)

allows enough distance to avoid competition between the individual maize

plants. Inter-row spacing (80 cm) provides an adequate distance for farmers’

access when weeding and harvesting.

Two seeds were planted per hole and later thinned to one 2 weeks

after planting (2 WAP). Following a common practice, the seeds were treated

with an insecticide prior to planting (Figure 53). The plot was weeded 2 WAP,

6 WAP, and 12 WAP (Figure 54). Leaves and small stems of Entada

abyssinica were cut, dried for three days, and applied again 6 WAP in the

same levels as the first application (1.25kg and 2.50kg). Maize was harvested

at physiological maturity, the husks removed, and weighed (wet weight)

including the cob by subplot to obtain yield (Figure 55). The preceding

activities are summarized in Table 2.

49

Figure 53 Sowing maize two seeds per hole. Photo by Brian Satterlee.

Figure 54 Weeding. Photo by Brian Satterlee.

Figure 55 Weighing maize. Photo by Brian Satterlee.

50

Activity Date (2006) WAP Labor hours

Soil samples April 18 N/A N/A

Clear plot May 22 week N/A 18.00

Cut Entada abyssinica May 30 N/A 8.50

Apply cuttings June 2 N/A 11.00

Sow maize June 9 N/A 7.00

Weed, thin maize June 26 2 10.00

Weed, cut Entada abyssinica July 19 6 16.00

Apply cuttings July 22 6 11.00

Soil samples August 14 10 N/A

Weed August 30 12 8.00

Harvest, weigh maize September 21 15 6.00

Soils Test Results November 24 N/A N/A

Table 2 Schedule and labor hours used for 0.11 hectare research plot.

Statistical Analysis

Analysis of variance (ANOVA) following Steele and Torrie

(1960) was conducted on the data set according to the experimental design

using the SAS (SAS Institute, 2003) procedures PROC UNIVARIATE,

PROC MEANS, PROC GLM, and PROC CORR. Means of soil properties

before and after treatment were tested with paired t-test and declared

significantly different at P < 0.10. Correlations using Pearson’s Correlation

51

were declared significant at P < 0.10. P values are reported throughout the

Results and Discussion chapter. Appendix B shows the SAS code used in the

statistical analysis of the data set.

52

CHAPTER 6 DATA

Data for this study consists of soil samples analyzed at IRAD

Nkolbisson and maize yield information, both from the trial plot in Luomo-

nangue. Results from soil sample analysis for clay content, fine silt content,

coarse silt content, total silt content, fine sand content, coarse sand content,

total sand content, organic carbon, nitrogen, organic matter, carbon to nitrogen

ratio, pH (water method), pH (KCl method), calcium, magnesium, potassium,

sodium, sum of bases, base saturation, available phosphorus, acidity, and

Cation Exchange Capacity (CEC) are represented in Table 3 through Table 26

respectively. The complete data set is shown in Appendix B.

The first soil samples (Test 1) were taken before any field

preparation for the trial began. The second samples (Test 2) were taken

approximately ten weeks after the trial began. Thus both applications of

Entada abyssinica cuttings had been applied and allowed to decompose prior

to the second soil samples being taken.

Table 3 Maize yield in kilograms by treatment

1 Difference = High value – low value throughout tables

Treatment Yield Average Difference1 A B C D E

26.74 30.37 20.80 37.96 20.14

5.35 6.07 4.16 7.59 4.03

7.92 4.62 5.28 5.28 4.29

Total 136.01

53

Table 4 Clay Content Percent

Table 5 Fine Silt Percent

Table 6 Coarse Silt Percent

Table 7 Total Silt Percent

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

25.08 18.50 19.20 22.50 20.76

10.70 23.60 8.40 12.70 6.40

36.00 35.20 34.62 35.52 33.48

12.90 5.80 4.00 10.10 3.60

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

26.88 27.34 28.54 25.86 30.46

10.70 5.10 4.70 7.70 14.80

26.96 24.88 25.82 26.26 25.58

6.90 6.50 4.30 4.80 6.50

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

24.54 23.94 25.58 30.44 22.76

5.80 2.60 3.50 12.30 14.30

12.60 12.94 12.54 15.44 15.64

5.00 4.20 3.30 3.00 2.40

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

51.42 51.28 54.10 56.26 53.20

14.70 4.20 5.00 15.40 4.10

39.58 37.82 38.38 41.72 41.24

4.30 5.80 7.70 6.00 7.90

54

Table 8 Fine Sand Percent

Table 9 Coarse Sand Percent

Table 10 Total Sand Percent

Table 11 Organic Carbon Percent

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

7.62 8.88 7.24 5.58 6.24

2.10 4.20 4.00 4.00 2.50

12.96 13.70 14.00 10.92 11.20

8.50 3.00 8.50 6.60 3.20

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

14.26 18.16 18.82 15.72 19.84

5.80 2.90 6.70 8.10 5.30

11.44 12.88 13.04 11.86 14.06

7.00 5.50 2.70 5.50 7.60

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

21.88 27.02 26.06 21.30 26.04

6.20 5.40 8.60 11.00 5.20

24.40 26.60 27.02 22.78 25.30

15.50 4.40 10.70 10.60 9.90

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

1.500 1.416 1.498 1.462 1.544

0.33 0.22 0.13 0.32 0.17

1.500 1.448 1.513 1.542 1.580

0.11 0.07 0.25 0.08 0.09

55

Table 12 Nitrogen Percent

Table 13 Organic Matter Percent

Table 14 C:N Ratio

Table 15 pH Water

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

0.350 0.394 0.408 0.332 0.408

0.16 0.14 0.30 0.08 0.26

0.384 0.384 0.380 0.348 0.332

0.21 0.07 0.15 0.13 0.13

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

2.5858 2.4412 2.5822 2.5206 2.6616

0.569 0.380 0.224 0.552 0.293

2.5862 2.4962 2.6102 2.6582 2.7240

0.189 0.121 0.413 0.138 0.155

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

4.38 3.66 3.88 4.40 3.92

2.40 1.30 2050 0.30 2.10

4.04 3.80 4.10 4.54 4.92

2.40 0.80 1.60 2.10 2.10

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

6.14 6.26 6.14 6.20 6.16

0.20 0.30 0.30 0.20 0.20

6.00 6.02 6.06 6.34 6.12

0.20 0.30 0.10 0.80 0.10

56

Table 16 pH KCl

Table 17 Calcium (cmol/kg)

Table 18 Magnesium (cmol/kg)

Table 19 Potassium (cmol/kg)

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

4.18 4.08 4.18 4.06 4.38

0.40 0.30 0.40 0.10 1.10

4.76 4.68 4.60 4.62 4.78

0.20 0.20 0.60 0.20 0.30

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

3.686 3.628 3.852 3.828 3.538

1.32 1.11 1.23 0.52 1.01

4.288 3.990 4.084 3.976 4.248

1.32 1.10 0.15 0.53 0.55

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

0.866 0.936 0.968 0.852 0.836

0.37 0.40 0.24 0.30 0.33

0.434 0.442 0.350 0.334 0.398

0.14 0.20 0.11 0.15 0.03

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

0.178 0.196 0.140 0.180 0.140

0.04 0.03 0.08 0.01 0.04

0.630 0.664 0.698 0.674 0.856

0.42 0.51 0.23 0.51 0.35

57

Table 20 Sodium (cmol/kg)

Table 21 Sum of Bases (cmol/kg)

Table 22 Cation Exchange Capacity (cmol/kg)

Table 23 Base Saturation Percent

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

0.056 0.078 0.040 0.070 0.052

0.03 0.05 0.06 0.05 0.02

0.124 0.126 0.134 0.126 0.146

0.07 0.11 0.04 0.09 0.06

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

5.038 5.310 4.276 4.930 4.566

1.39 0.32 1.54 0.97 1.34

5.264 5.584 5.116 5.108 5.648

1.00 1.27 0.37 0.82 0.48

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

24.08 27.00 28.92 25.20 27.44

7.50 6.50 7.40 13.00 9.30

26.76 24.10 16.96 22.54 24.66

12.40 7.10 13.40 12.80 3.00

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

21.20 19.80 15.00 20.40 16.80

4.00 6.00 8.00 9.00 4.00

20.40 23.40 33.20 24.00 23.00

8.00 12.00 25.00 15.00 4.00

58

Table 24 Available Phosphorus (ppm)

Table 25 Acidity (cmol/kg)

Table 26 ECEC (cmol/kg)

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

6.86 5.60 7.40 6.30 7.06

2.60 6.20 5.30 5.70 3.20

8.38 9.00 7.54 7.66 11.22

4.00 18.10 4.50 5.00 13.00

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

1.454 1.152 1.610 1.618 0.924

1.15 1.74 2.33 1.16 1.16

0.604 0.940 0.830 0.862 1.196

1.21 0.62 0.61 0.74 1.18

Treatment Test 1 Average

Test 1 Difference

Test 2 Average

Test 2 Difference

A B C D E

6.492 6.462 5.886 6.548 5.490

0.55 1.69 3.43 0.78 2.22

5.868 6.524 5.946 5.970 6.844

0.41 1.73 0.87 0.67 1.28

59

SECTION 3

IMPLICATIONS OF STUDY

60

CHAPTER 7 RESULTS AND DISCUSSION

Leguminous plants produce sufficient amounts of biomass which

can be used as green manure to release nutrients into the soil and improve soil

physical properties. As a result, soil fertility is increased, inorganic fertilizer

use can be reduced, and crop yields can be improved naturally (Ogunnika,

2005). For example, Entada abyssinica leaves, raches, and petioles contain

2.99% N, 0.30% P, 0.75% K, 2.58% Ca, and 0.46% Mg (Anthofer et al.,

1998). In this experiment maize yield and some soil properties experienced

significant differences depending on the application method, the amount, and

the interaction between these two variables as a direct result of Entada

abyssinica’s use as green manure.

Maize Yield

Yield depended upon how the cuttings were incorporated. Mixed

incorporation generated 3.76 metric tons/hectare (Figure 56), which was

significantly greater than mulching and the control (P = 0.0613). Mulching

and the control were not significantly different from each other. Additionally,

mixing a higher quantity of Entada abyssinica cuttings showed a significant

correlation to yield and generated 4.22 metric tons/hectare, the highest of the

four treatments and higher than the control (Figure 57), (r = 0.45, p = 0.02).

61

Figure 56 Maize yield (metric tons/hectare) by treatment

Maize YieldMean and Standard Error

0.001.002.003.004.005.00

Control Mix Mulch

Treatment

Met

ric to

n/ha

Figure 57 Maize Yield by treatment

Maize YieldMean and Standard Error

0.001.002.003.004.005.00

A B C D E

Treatment

Met

ric to

n/ha

In a related study by Mugendi et al. (1999b) in the Eastern Province

of Kenya, similar quantities of Leucaena leucocephala cuttings mixed into the

soil without supplemental inorganic fertilizer generated over four metric

tons/hectare maize grain yield. Mixing rather than mulching resulted in higher

maize yields as well in a field trial by Kang et al. (1981b) in southern Nigeria.

In this experiment using Entada abyssinica cuttings, mixing resulted in

highest yields.

However, these findings are not consistent with other trials

involving different application methods of leguminous cuttings. Read et al.

62

(1985) used eight treatments with five replications in a randomized complete

block design in southwest Nigeria. No difference in maize yield was shown

between the two methods. Similarly, an alley cropping experiment in Haiti by

Isaac et al. (2004) found no maize yield increase when cuttings applied were

mixed or mulched.

Economically, this trial indicates that adopting the practice of green

manure with Entada abyssinica can have enormous, rapid results for

smallholder farmers in the Adamawa. For example, assume that a 100 kg sack

of maize costs 9,000 FCFA ($US 18.33)2 and a farmer uses a quarter hectare

for maize cultivation. Compared to the control plot yield, mixing Entada

abyssinica cuttings at a rate of 347 kg per quarter hectare would result in an

additional three sacks of maize valued at 27,000 FCFA ($US 54.99). Even

after subtracting the additional labor cost of mixing the cuttings with a hoe

(6000 FCFA, $US 12.22), the farmer is left with an extra 21,000 FCFA

($US 42.77). This additional revenue could pay for fees and supplies for a

secondary school student for an entire year.

Soil Properties

Plants require seventeen essential elements in order to grow and

reproduce. Generally, these elements are crucial to plant survival and cannot

be replaced by other elements. They are classified as either macronutrients or

micronutrients based on the plant requirement (Jones and Jacobsen, 2005).

Despite a lack of formal agricultural education, farmers in the

2 1$US = 491 FCFA on 3/22/2007 (Source: http://www.xe.com/ucc/convert.cgi)

63

Adamawa are knowledgeable about the benefits of nitrogen, potassium, and

phosphorous to their crop yields. They know that these three elements

comprise the majority of maize’s macronutrient demands (Leonard, 1981).

Unfortunately, NPK chemical fertilizers are generally beyond their means and

even when purchased are used at levels well below those recommended.

In most of the tropics and particularly in Africa, nitrogen deficiency

is the single most limiting factor to crop yields (Mugendi et al, 1999b). In this

experiment, no statistically significant differences among the treatments and

the control were found for nitrogen (P = 0.5287). Nitrogen percent

Differenced from 0.332% to 0.408% before Entada abyssinica cuttings were

applied and 0.332% to 0.384% five weeks before maize harvest (Table 27).

According to a soil scientist from IRAD Nkolbisson who analyzed the soil

samples, initial nitrogen levels can be considered very high in all treatments

and the control in this experiment (Yemefack, 2006).

Table 27 Nitrogen percent by treatment

Treatment Test 1 Test 2

A 0.350 0.384 B 0.394 0.384 C 0.408 0.380 D 0.332 0.348 E 0.408 0.332

Notes Test 1 = Results from soil samples taken prior to cutting application

Test 2 = Results from soils samples taken five weeks before maize harvest

64

Potassium promotes starch and sugar formation, stalk and root

growth, and ear development (Leonard, 1981). Potasssium levels increased

significantly across all treatments and the control in this experiment

(Table 28). The control treatment increased over 250%, due perhaps to a crop

residue collected in the second soil samples. Treatment B through Treatment

E increased 239%, 399%, 274%, and 511% respectively. Several studies

support similar findings when using agroforestry species to improve soil

properties. Raddad et al. (2005) reported K increases when Acacia senegal

was used for improved fallow while Kang et al. (1999) found higher soil

potassium concentration in a long term alley cropping trial with four different

hedgerow species in Nigeria. When the cuttings were mulched potassium

showed a significant increase and higher final levels (P = 0.0635).

Table 28 Potassium percent by treatment

Treatment Test 1 Test 2

A 0.178 0.630 B 0.196 0.664 C 0.140 0.698 D 0.180 0.674 E 0.140 0.856

Notes Test 1 = Results from soil samples taken prior to cuttings application

Test 2 = Results from soils samples taken five weeks before maize harvest

65

Phosphorous is important for root growth, flowering, and seed

formation (Leonard, 1981). Maize grown on phosphorous deficient soils

suffer from stunting, delayed maturity, and poor ear development

(Crozier, 2000). In this experiment, mulching 2.50 kg of Entada abyssinica

showed a significant increase for P (Table 29). Treatment B through

Treatment E increased 60.71%, 1.89%, 21.59%, and 58.92 % respectively

while the control increased 22.16%. Kaho et al. (2004) also found available P

to increase in soil samples taken at 0 to 15cm depths over four years under a

Desmodium distortum fallow trial in Cameroon’s Center province. Leaching

of phosphorous from agricultural soils is generally low due to its insolubility

and could be a factor in the increase (Stevenson, 1986).

Table 29 Phosphorous (ppm) by treatment

Treatment Test 1 Test 2

A 6.86 8.38 B 5.60 9.00 C 7.40 7.54 D 6.30 7.66 E 7.06 11.22

Notes Test 1 = Results from soil samples taken prior to cuttings application Test 2 = Results from soils samples taken five weeks maize harvest

66

An additional problem concerning NPK chemical fertilizers

occurred in both the 2005 and 2006 cropping season in Mbang-Mboum and

surrounding villages. Four GICs (Groupe d’Initiative Communitaire) pooled

their resources and purchased chemical fertilizer through an NGO located in

Ngaoundéré, the district capital. The shipment did not arrive in time for timely

field application and farmers sowed maize without it. Two whole seasons’

maize crop yield was drastically reduced. According to the results of this

experiment, the use of Entada abyssinica could have at least partly reduced

this loss.

Exposure to the use of tree litter as an organic soil fertility

improvement method has been minimal in the Adamawa. Farmers are

unaware of its ability to enhance the microclimate and its effectiveness in

suppressing weed growth. Their use of crop residues and cattle manure

during the dry season, however, indicates an understanding of organic matter

use to improve soil fertility. It is natural, inexpensive, and sustainable and has

been utilized throughout the province for decades.

The soils tests results showed organic matter buildup as a result of

Entada abyssinica use and could be a valuable complement to farmers’

traditional practices (Table 30). Additionally, significant differences were

found between how the cuttings were incorporated (P = 0.0559) and amount

of cuttings applied (P = 0.0060). Ogunnika et al. (2005) found organic matter

soil content to increase as well when soil including four nitrogen-fixing trees’

leaf fall was compared with untreated farmland soil in southwest Nigeria.

67

Conversely, Aweto and Iyanda (2003) found no significant increase in organic

matter in soils under thirty Newbouldia laevis trees in ten plots in

southwestern Nigeria.

Table 30 Organic matter percent by treatment

Treatment Test 1 Test 2

A 2.586 2.586 B 2.441 2.496 C 2.582 2.610 D 2.521 2.658 E 2.662 2.724

Notes Test 1 = Results from soil samples taken prior to cuttings application

Test 2 = Results from soils samples taken five weeks before maize harvest

Besides increasing soil fertility, organic matter contributes to soil

aggregation, aids in reducing erosion, and helps prevent micronutrient

leaching (Sanchez, 1976). Every farmer should strive to increase the organic

matter in his or her farm (Kohnke, 1966). However, adoption depends on

expected returns and particularly the speed at which these returns are realized

(Scoones and Toulmin, 1999). This trial, over a single cropping season,

indicates immediate soil characteristics improvement by including organic

matter in farmers’ cropping systems and could potentially help increase

adoption rates in the Adamawa. Kang et al. (1999) showed that the use of

organic matter in Nigeria could maintain soil productivity over the long-term

as well.

68

Organic carbon is a component of organic matter and provides an

energy source for soil microorganisms. These microorganisms in turn assist in

the decomposition of organic matter (Howell, 2004). In this trial the organic

carbon was found to vary significantly with amount of cuttings applied

(P = 0.0076). A greater quantity of cuttings will result in greater organic

carbon availability. In a field trial in Ibadan, Nigeria, Kang et al. (1985)

applied Leucaena leucocephala cuttings over a six year period and found

organic carbon soil content to increase each year and by 65% overall.

Changes in other soil property and related fertility indicators in this

trial were shown to be significant. Decreases were shown for pH (water

method), magnesium, and CEC. The carbon to nitrogen ratio (C:N Ratio), pH

(KCl method), calcium, sodium, sum of bases, and base saturation showed

significant increases. No significant block impact was found. It was included

in the experimental design as the study size was originally larger but later

reduced. Soil property changes in the control plots are a result of

macronutrient and micronutrient demands and additions of the associated

maize crop.

Table 31 summarizes the results found from the statistical analysis

of this data set. Correlation results reinforce those found by the analysis of

variance.

69

Table 31 ANOVA declared significantly different at P < 0.10. Values in red are significant. Decreases denoted with * symbol.

ANOVA

VARIABLE HOWINC AMOUNT HOWINC*AMOUNT Yield 0.0613 0.5226 0.4478 N 0.7372 0.1670 0.8388 K 0.0635 0.1334 0.1827 P 0.5152 0.4691 0.1312 OM 0.0559 0.0060 0.5882 OC 0.1255 0.0076 0.5705 Ca 0.2312 0.6181 0.5548 Mg 0.2363 0.2965 0.0127* C:N Ratio 0.3565 0.0531 0.8938 pH (water method) 0.1415 0.0173* 0.0880* pH (KCl method) 0.4247 0.3828 0.0916 Na 0.1653 0.5420 0.5420 Sum of Bases 0.8290 0.8602 0.0053 CEC 0.0696* 0.1341 0.0301 Base Saturation 0.0674 0.0841 0.0548

Notes HOWINC = How the cuttings were incorporated AMOUNT = Amount (kg) of cuttings applied HOWINC*AMOUNT = Interaction between how the cuttings were incorporated and amount of cuttings applied

Data from Table 31 indicates that this one year study improved

maize yield and soil properties with the use of Entada abyssinica cuttings as

green manure. Mixing the cuttings resulted in significantly higher maize

yields. In addition, greater amounts of cuttings significantly increased organic

matter. As a result, the soil in this trial became less acidic as indicated by an

increase in pH (KCl method). The reduced acidity made soil nutrients more

readily available. Potassium and sodium increased significantly. As

70

components in determining a soil’s base saturation and sum of bases, it

follows that these two soil fertility indicators increased as well. Magnesium

levels were originally low, supported by low calcium to magnesium ratios.

The associated maize crop’s demand for this nutrient may have caused it to

decrease significantly.

How the cuttings were applied impacted yield, potassium, organic

matter, pH (water method), CEC, and base saturation. Amount showed

significant increases for organic matter and organic carbon. The interaction

between how the cuttings were applied and amount of cuttings affected

magnesium as well as sum of bases, CEC, and base saturation.

71

CHAPTER 8 CONCLUSIONS AND RECOMMENDATIONS

Farmers in the Adamawa province lead a simple but extremely hard

life. Days begin before dawn with a hike to their farms, perhaps after a cup of

tea. Once there, they engage in exhausting work including tilling and weeding

with tools often considered to be primitive. Returning to their mud huts at

dusk, they eat, socialize, and bed down for the night. The cycle continues day

after day.

Subsistence farmers’ small scale farms and home gardens provide

not only their food source but their income as well. Generally, any excess is

sold at the weekly market and the revenue used to pay school fees and taxes,

buy clothing, help an ill family member, and maybe a rare trip to the district

capital. This is not a life of excess.

Population pressure is jeopardizing traditional farming practices in

the Adamawa. Without methods to maintain fertility, soils are depleted of

valuable nutrients necessary to sustain adequate crop yields. To compound the

problem, chemical fertilizers are beyond the means of most farmers.

This study shows that the incorporation of cuttings from a local,

indigenous, abundant tree species is a viable alternative to chemical fertilizer

use. Not only did Entada abyssinica cuttings increase maize yield when mixed

with the soil, but also increased organic matter and potassium, and raised soil

pH levels. More importantly, these results occurred in the same cropping

season.

72

A common shortcoming of development work is that it fails to take

into consideration the needs, wants, and desires of the local community that

the project aims to serve. As a member of the village of Mbang-Mboum for

over two years, I personally spoke to over 700 farmers and was told that

improving maize yield, immediately, was their primary objective. Fertile soil

would help, but higher maize productivity was paramount (Bunch, 1999).

This study was designed in response to the most important needs of

these rural farmers. It utilized a native tree species familiar to most villagers.

Commonly known as pade waandu, or monkey sandals due to the shape of its

leaflets, it is used in pottery making, provides traditional medicines, and

boundary demarcation. Another use for an existing input was simply shared.

Furthermore, results were immediate. The additional labor required to mix the

Entada abyssinica cuttings would pay off in the same cropping season as well.

Three additional sacks of maize valued at 21,000 FCFA ($US 42.77) could be

realized at harvest from a quarter hectare of land.

Short term results emphasizing indigenous tree species is crucial to

adoption rates. These adoption rates in turn provide for the sustainability of

agricultural development (Bunch, 1999). This study satisfies both these

requirements and could be a successful method to increase farmer’s income in

the Adamawa.

Farmers in the Forgotten Province will continue to live with or

without outside assistance. They will persist through droughts, pest

infestations, births, and deaths as they have for centuries. However, if they can

73

be convinced to adopt the appropriate agroforestry technique, they might be

recognized as the people that built their own capacity by taking a chance. And

that won’t be easily forgotten.

74

LITERATURE CITED

Additional uncited literature found in Appendix A

Ahmadou, Abu. 2004. Interview by author, Mbang-Mboum, Cameroon, December 2004.

Anthofer, J., J. Hanson, and S.C. Jutzi . 1998. Wheat growth as influenced by application of agroforestry-tree prunings in Ethiopian highlands. Agroforestry Systems 40: 1-18.

Aweto, A.O., and A.O. Iyanda. 2003. Effects of Newbouldia leavis on soil subjected to shifting cultivation in the Ibadan area, southwestern Nigeria. Land Degradation and Development 14: 51-56.

Beets, Willem C. 1990. Raising and Sustaining Productivity of Smallholder Farming Systems in the Tropics. AgBé Publishing, Holland. 738 pp.

Bunch, Roland. 1999. Reasons for non-adoption of soil conservation technologies and how to overcome them. Mountain Research and Development 19 (3): 213-220.

Christensen, Cheryl. 1994. Agriculture Research in Africa. A Review of USAID Strategies and Experience. Economic Research Service. U.S. Department of Agriculture. On line: http://pdf.usaid.gov/pdf_docs/PNABT363.pdf. Site visited12/12/2006.

CIA (Central Intelligence Agency), U.S. 2006. The World Factbook-Cameroon. On line: https://www.cia.gov/cia/publications/factbook/geos/cm.html. Site visited 12/3/2006.

Crozier, Carl R. 2000. Fertilizer and Lime Management. The North Carolina Corn Production Guide. North Carolina State University Cooperative Extension Service. On-line: http://www.ces.ncsu.edu/plymouth/cropsci/cornguide/. Site visited 2/22/2007.

FAO (Food and Agriculture Organization). 2006. Entada abyssinica fact sheet. Corporate Document Repository. On line: http://www.fao.org/docrep/X5327E/x5327e10.htm. Site visited 12/11/2006.

Hino, Sun’ya. 1984. Social relation between towns and villages in Adamawa regional society. A Case Study of Ngaoundéré and Mbang-Mboum. On line: horizon.documentation.ird.fr/exldoc/pleins_textes/pleins_textes_6/colloques2/40393.pdf. Site visited 11/17/2006.

75

Howell, John. 2004. Soil and Nutrient Management. University of Massachusetts Extension Vegetable Program. On line: http://www.umassvegetables.org/soil_crop_pest_mgt/soil_nutrient_mgt_/soil_basics__I.html. Site visited 8/21/2004. Isaac, Lionel, Dennis A. Shannon, and C. Wesley Wood. 2004. Nutrient cycling. Hedgerow pruning management effects on maize yield and nitrogen uptake in an alley cropping system in Haiti. Agronomy Journal 96: 1632-1640.

Jones, Clain and Jeff Jacobsen. 2005. Plant Nutrition and Soil Fertility. Nutrient Management Module Number 2. Montana State University. On-line: http://www.montana.edu/wwwpb/pubs/mt44492.pdf. Site visited 2/21/2007. Kaho, F., M. Yemefack, B.A.K. Nguimgo, and C.G. Zonkeng. 2004. The effect of short rotation Desmodium distortium planted fallow on the productivity of utisols in centre Cameroon. Tropicultura 22 (2): 49-55. Kaho, Francois, Martin Yemefack, and James Quashite-Sam. 2002. Soil fertility changes under Leucaena leucocephala woodlot and their consequences on the succeeding crop in the humid forest zone of Ghana. Nigeria Journal Soil Resources 3: 39-44. Kang, B.T., G.F. Wilson, and L. Sipkens. 1981a. Alley cropping maize (Zea mays L.) and Leucaena (Leucaena leucocephala Lam) in southern Nigeria. Plant and Soils 63: 165-179. Kang, B.T., L. Sipkens, G.F. Wilson, and D. Nangju. 1981b. Leucaena (Leucaena leucocephala (Lam de Wit)) prunings as a source for maize (Zea mays L.). Fertilizer Research 2: 279-287. Kang, B.T., H. Grimme, and T.L. Lawson.1985. Alley cropping sequentially cropped maize and cowpea with Leucaena on a sandy soil in southern Nigeria. Plant and Soil 85: 267-277. Kang, B.T., F.E. Caveness, G. Tian, and G.O. Kolawole. 1999. Longterm alley cropping with four hedgerow species on an alfisol in southwestern Nigeria-effect on crop performance, soil chemical properties and nematode population. Nutrient Cycling in Agroecosystems 54: 145-155.

Kohnke, Helmut. 1966. Soil Science Simplified. Waveland Press Inc., Prospect Heights, Illinois. 78 pp.

76

Leonard, David. 1981. Traditional Field Crops. Peace Corps Information Collection and Exchange, Washington, D.C. 386 pp.

Mapongmetsem, Pierre Marie, L.B. Benoit, B.A. Nkongmenteck, N.B. Ngassoum, H. Gübbük, C. Baye-Niwah, and J. Longmou. 2005. Litterfall, decomposition, and nutrients release in Vitex doniana Sweet. and Vitex madiensis Oliv. in the Sudano-Guinea savannah. Akdeniz Üniversitesï Zіraat Fakültesï Dergisi 18 (1): 63-75.

Mugendi, D.N., P.K.R. Nair, J.N. Mugwe, M.K. O’Neill, M.J. Swift, and P.L. Woomer. 1999a. Alley cropping of maize with calliandra and leucaena in the subhumid highlands of Kenya. Part 1. Soil Fertility Changes and Maize Yield. Agroforestry Systems 46: 39-50.

Mugendi, D.N., P.K.R. Nair, J.N. Mugwe, M.K. O’Neill, and P.L. Woomer. 1999b. Alley cropping of maize with calliandra and leucaena in the sub humid highlands of Kenya. Part 2. Biomass decomposition, N mineralization, and N uptake by maize. Agroforestry Systems 46: 51-64. Nyamnjoh, Francis B. 1999. Cameroon: A country united by ethnic ambition and difference. African Affairs 98: 101-118. Ogunnika, C.B. and J.O. Kayode. 2005. Contributions of nitrogen-fixing trees (NFTs) to soil physico-chemical properties in humid forest region in Nigeria. Journal of Food, Agriculture, & Environment 3: 142-146.

Onguene, N.A. and T.W. Kuyper. 2001. Mycorrhizal associations in the rainforest of south Cameroon. Forest Ecology and Management 140: 277-287.

Peace Corps, U.S. 2002. Cameroon. A Peace Corps Publication for New Volunteers. Volunteer Invitee Packet. 91 pp. Raddad, E.Y., O. Luukkanen, A.A. Salih, V. Kaarakka, and M.A. Elfadl. 2005. Productivity and nutrient cycling in young Acacia senegal farming systems on vertisol in the Blue Nile region, Sudan. Agroforestry Systems 68: 193-207. Read, M.D., B.T. Kang, and G.F. Wilson. 1985. Use of Leucaena leucocephala (Lam de Wit) leaves as a nitrogen source for crop production. Fertilizer Research 8: 107-116. Rukangira, Ernest. 2004. The African Herbal Industry: Constraints and Challenges. On line: http://www.conserveafrica.org.uk/herbal_industry.pdf. Site visited 1/17/2007.

77

Sanchez, Pedro A. 1976. Properties and Management of Soils in the Tropics. John Wiley and Sons. New York. 618 pp.

Scoones, Ian and Camilla Toulmin. 1999. Policies for Soil Fertility Management in Africa. Russell Press. Nottingham. 128 pp. State Department, U.S. 2006. Bureau of African Affairs. Background note: Cameroon. On line: http://www.state.gov/r/pa/ei/bgn/26431.htm. Site visited 1/12/2007. Steele, Robert G.D., and James H Torrie. 1960. Principles and Procedures of Statistics. McGraw-Hill. New York. 481 pp. Stevenson, F. J. 1986. Cycles of Soil. Carbon, Nitrogen, Phosphorous, Sulfur, Micronutrients. John Wiley and Sons. New York. 380 pp.

Swartz, B.K. 1989. The Eton pottery industry of Nkol-Nguele Village, Central Province, Cameroon. West African Journal of Archaeology 19: 117-36. Thurston, H. David. 1997. Slash/Mulch Systems. Westview Press. Boulder, Colorado. 196 pp. Transparency International. 1999. The Transparency International Corruption Perceptions Index. On line: http://www.transparency.org/policy_research/surveys_indices/cpi/previous_cpi__1/1999. Site visited 11/17/2006.

Wolf, Hans-Georg. 2001 English in Cameroon. Walter de Gruyter. Berlin and New York. 359 pp.

World Agroforestry Center. 2006. Agroforestry Tree Database. International Center for Research in Agroforestry. On line: http://www.worldagroforestrycentre.org/sea/products/afdbases/af/asp/SpeciesInfo.asp?SpID=730#Ecology. Site visited 3/15/2007.

World Bank. 2006. Country Brief. Cameroon. On line: http://web.worldbank.org/WBSITE/EXTERNAL/COUNTRIES/AFRICAEXT/CAMEROONEXTN/0,,menuPK:34381. Site visited 1/16/2007. Yebit, George, 2004. Cameroon Agroforestry & Permanent Farming Systems Project Plan. Peace Corps Cameroon Information Exchange. 40 pp.

Yemefack, Martin. 2006. Soil sample analysis. IRAD Nkolbisson office.

78

Appendix A

Additional Uncited Literature

Akobundu, I.O., F. Ekeleme, and D. Chikoye. 1999. Influence of fallow management system and frequency of cropping on weed growth and crop yield. Weed Research 39: 241-256. Arias, Eliezer. 2005. Agricultural market reforms and potato farmers’ strategies in the Pueblo Llano Valley Venezuelan Andes. Mountain Research and Development. 25 (4): 357-364. Barley, Nigel. 1983. The Innocent Anthropologist. Waveland Press Inc. Prospect Heights, Illinois. 190pp. Blaise, Guy and Nkamleu Ngassan. 1999. Etat des lieux de l’agroforestrie au Cameroon: cas des provinces du Centre, du Sud-Ouest et du Nord-Ouest. Secheresse 10 (3): 165-170. Brenes, Alvaro Brenes. 2005. A review of the agroforestry systems of Costa Rica. Journal of Sustainable Forestry 21 (1): 97-119. Buresh, R.J. and G. Tian. 1998. Soil improvement by trees in sub-Saharan Africa. Agroforestry Systems 38: 51-76. Caamal-Maldonado, Jesus Arturo, Juan José Jiménez-Osornio, Andrea Torres-Barragán, and Ana Luisa, Anaya. 2001. The use of allelopathie legume cover and mulch species for weed control in cropping systems. Agronomy Journal 93: 27-36. Chintu, R., P.I. Mafomgoya, T.S. Chirwa, M. Mwale, and J. Matibini. 2004. Subsoil nitrogen dynamics as affected by planted coppicing tree legume fallows in eastern Zambia. Experimental Agriculture 10: 327-340. Chomba, Gilbert. 1999. Quelle politique pour le monde d’agricole. Jeune Afrique Economie. Du 1er Au 14 Fevrier. 62-66. Ferguson, Richard B., Kenneth D. Prank, Gary W. Hergert, Edwin J. Penas, and Richard A. Wiese. 1998. Guidelines for Soil Sampling. University of Nebraska-Lincoln, Cooperative Extension, Institute of Agriculture and Natural Resources. On-line: http://ianrpubs.unl.edu/Soil/g1000.htm. Site visited 12/28/2005

79

Garner, R.J. and Saeed Ahmed Chaudhri. 1976. The Propagation of Tropical Fruit Trees. C.A.B. International. England. 566 pp. Geschiere, Peter. 1997. The Modernity of Witchcraft. The University Press of Virginia. Charlottesville and London. 311 pp.

Gifford, Prosser and William Roger Louis. 1988. Decolonization and African Independence 1960-1980. Yale University Press. New Haven and London. 651 pp.

Hance, William A. 1975. The Geography of Modern Africa. Columbia University Press. New York and London. 657 pp. Jiang, P. and K.D. Thelen. 2003. Effect of soil and topographic properties on crop yield in a north-central corn-soybean cropping system. Agronomy Journal 96: 252-258. Johnson, James E. and Orlando J. Delgado. 2005. Agroforestry adoption potential in Cape Verde. Small-Scale Forest Economics, Management and Policy, 4(2): 205-214 Knight, C. Gregory and James L. Newman. 1976. Contemporary Africa: Geography and Change. Prentice-Hall, Inc. Englewood Cliffs, New Jersey. 546 pp. Lewis, William H. 1965. French-Speaking Africa: The Search for Identity. Walker and Company. New York. 256 pp. Mahler, R.L. and T.A. Tindall. 1990. Soil Sampling Bulletin 704. University of Idaho, Cooperative Extension System, College of Agriculture. Mercer, D.E. 2004. Adoption of agroforestry innovations in the tropics: A review. Agroforestry Sysems 204411: 311-328. Nair, P.K.R. 1998. Directions in tropical agroforestry research: past, present, and future. Agroforestry Systems 38: 223-245.

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Appendix B

SAS code used for statistical analysis of the data set

ANOVA proc glm; class HOWINC AMOUNT BLOCK ; model YIELD = HOWINC AMOUNT BLOCK HOWINC*AMOUNT ; means HOWINC AMOUNT /tukey alpha=.1 ; proc end; Paired T Test PROC MEANS N MEAN STDERR T PRT ; VAR DOMA; RUN; Descriptive statistics PROC UNIVARIATE ; VAR TREATA TREATB TREATC TREATD TREATE BLOCK AMOUNT HOWINC YIELD OC1 OC2 N1 N2 OM1 OM2 CN1 CN2 PHW1 PHW2 PHKCL1 PHKCL2 CA1 CA2 MG1 MG2 K1 K2 NA1 NA2 SUMBASE1 SUMBASE2 CEC1 CEC2 BASESAT1 BASESAT2 AVAILP1 AVAILP2 ACIDITY1 ACIDITY2 ECEC1 ECEC2 ; RUN;

82

Correlation PROC CORR ; VAR TREATA TREATB TREATC TREATD TREATE BLOCK AMOUNT HOWINC YIELD OC1 OC2 N1 N2 OM1 OM2 CN1 CN2 PHW1 PHW2 PHKCL1 PHKCL2 CA1 CA2 MG1 MG2 K1 K2 NA1 NA2 SUMBASE1 SUMBASE2 CEC1 CEC2 BASESAT1 BASESAT2 AVAILP1 AVAILP2 ACIDITY1 ACIDITY2 ECEC1 ECEC2 ; RUN;

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Appendix C Soil sample results from analysis at IRAD Nkolbisson, Yaoundé, Cameroon. Test 1 from 5/2006. Test 2 from 9/2006.

Sample Corn Yield Clay Test1 Clay Test2 Fine Silt Test1 Fine Silt Test2 Coarse Silt Test1 Coarse Silt Test2 YIELD CLAY1 CLAY2 FSILT1 FSILT2 CSILT1 CSILT2 A1 3.5 30.4 39 24.4 28.2 27.1 10.6 A2 6.8 26.3 41.4 28.3 27.2 21.3 14.4 A3 2.18 19.7 38.3 30.4 25.7 25.7 11.6 A4 4.16 28 32.8 20.3 30.3 22.3 10.8 A5 10.1 21 28.5 31 23.4 26.3 15.6 B1 7.13 21.5 38.3 29.5 25.1 23.7 10.8 B2 6.8 23.6 37.3 26.8 23.1 22.5 14.6 B3 8.12 21.8 35.8 24.4 25.1 24.8 11.4 B4 3.5 24.6 32.5 27.7 28.8 23.6 12.9 B5 4.82 1 33.7 28.3 22.3 25.1 15 C1 4.16 18.1 37 30.7 28.6 26.1 13.7 C2 0.86 25 33 28.2 24.3 23.5 13 C3 6.14 18.6 33 26 24.6 27 13.3 C4 4.16 20.8 34 29.8 24.3 26.9 10.4 C5 5.48 16.6 36.1 28 27.3 24.4 12.3 D1 7.46 24.2 40.5 24.7 26.1 23.5 15.2 D2 10.1 29.4 34.7 23.5 28.8 28.8 16.2 D3 7.46 24.5 39.7 30.3 25.2 28.6 16.9 D4 4.82 16.7 32.3 28.2 24 35.5 15 D5 8.12 17.7 30.4 22.6 27.2 35.8 13.9 E1 3.5 20.5 35.1 26.9 26.7 24 17.4 E2 2.84 18.5 31.5 28.1 25.8 26.9 15.3 E3 3.5 24.6 33 28.4 20.8 23.6 15.5 E4 7.13 18.2 33.9 27.2 27.3 26.7 15 E5 3.17 22 33.9 41.7 27.3 12.6 15

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Sample Total Silt Test1 Total Silt Test2 Fine Sand Test1 Fine Sand Test2 Coarse Sand Test1 Coarse Sand Test2

TSILT1 TSILT2 FSAND1 FSAND2 CSAND1 CSAND2 A1 51.5 38.8 8.1 12.7 10.1 9.5 A2 49.7 41.6 8.2 8.8 15.8 8.2 A3 56 37.3 8.4 12.3 15.9 12.1 A4 42.6 41.2 6.3 13.7 15.1 12.2 A5 57.3 39 7.1 17.3 14.4 15.2 B1 53.2 35.9 7.9 14.5 17.4 11.3 B2 49.2 37.7 8.1 13.3 19.2 11.3 B3 49.2 36.5 11.4 15.2 17.7 12.4 B4 51.4 41.7 7.2 13.3 16.8 12.6 B5 53.4 37.3 9.8 12.2 19.7 16.8 C1 56.7 42.4 6.9 9.3 18.2 11.3 C2 51.7 37.4 8.2 16.6 15.1 13.2 C3 53 37.9 6.7 15.1 21.8 14 C4 56.7 34.7 5.2 17.8 17.2 13.5 C5 52.4 39.5 9.2 11.2 21.8 13.2 D1 48.2 41.3 7.3 8.9 20.3 9.3 D2 52.2 45 4.6 8.8 14 11.5 D3 58.9 42.2 4.4 8.2 12.2 9.9 D4 63.6 39 3.8 13.9 15.9 14.8 D5 58.4 41.1 7.8 14.8 16.2 13.8 E1 50.9 44.2 6.6 9.5 22.1 11.3 E2 55 41.1 5.8 12.7 20.7 14.7 E3 52 36.3 6.7 11.8 16.8 18.9 E4 53.9 42.3 7.3 11 20.6 12.7 E5 54.2 42.3 4.8 11 19 12.7

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Sample Total Sand

Test1 Total Sand

Test2 OC Test1 OC Test2 N Test1 N Test2 Organic Matter Test1 Organic Matter Test2 TSAND1 TSAND2 OC1 OC2 N1 N2 OM1 OM2

A1 18.2 22.2 1.39 1.53 0.33 0.41 2.396 2.638 A2 23.9 17 1.4 1.48 0.31 0.49 2.414 2.552 A3 24.4 24.4 1.47 1.55 0.35 0.4 2.534 2.672 A4 21.4 25.9 1.72 1.44 0.3 0.34 2.965 2.483 A5 21.5 32.5 1.52 1.5 0.46 0.28 2.62 2.586 B1 25.3 25.9 1.43 1.43 0.41 0.36 2.465 2.465 B2 27.2 24.6 1.26 1.47 0.37 0.35 2.172 2.534 B3 29 27.7 1.48 1.49 0.34 0.42 2.552 2.569 B4 24.1 25.8 1.47 1.43 0.48 0.42 2.534 2.465 B5 29.5 29 1.44 1.42 0.37 0.37 2.483 2.448 C1 25.2 20.6 1.55 1.53 0.6 0.44 2.672 2.638 C2 23.3 29.7 1.43 1.4 0.4 0.3 2.465 2.414 C3 28.4 29.1 1.43 1.6 0.36 0.35 2.465 2.758 C4 22.4 31.3 1.56 1.4 0.38 0.45 2.689 2.414 C5 31 24.4 1.52 1.65 0.3 0.36 2.62 2.827 D1 27.6 18.2 1.57 1.52 0.35 0.39 2.707 2.62 D2 18.6 20.3 1.26 1.52 0.29 0.4 2.172 2.62 D3 16.6 18.1 1.58 1.54 0.37 0.34 2.724 2.655 D4 19.7 28.7 1.46 1.6 0.34 0.27 2.517 2.758 D5 24 28.6 1.44 1.53 0.31 0.34 2.483 2.638 E1 28.6 20.8 1.56 1.53 0.44 0.28 2.689 2.638 E2 26.5 27.4 1.49 1.59 0.37 0.34 2.569 2.741 E3 23.4 30.7 1.56 1.62 0.31 0.26 2.689 2.793 E4 27.9 23.8 1.47 1.58 0.35 0.39 2.534 2.724 E5 23.8 23.8 1.64 1.58 0.57 0.39 2.827 2.724

86

Sample C:N Ratio Test1 C:N Ratio Test2 pH Water Test1 pH Water Test2 pH KCL Test1 pH KCL Test2 Ca Test1 Ca Test2

CN1 CN2 PHW1 PHW2 PHKCL1 PHKCL2 CA1 CA2 A1 4.2 3.7 6.2 6 4.4 4.8 4 3.96 A2 4.5 3 6.2 6 4 4.7 4.08 5.1 A3 4.2 3.9 6.1 6.1 4 4.9 3.99 4.6 A4 5.7 4.2 6 6 4.3 4.7 3.6 4 A5 3.3 5.4 6.2 5.9 4.2 4.7 2.76 3.78 B1 3.5 4 6.2 5.9 4 4.8 3.1 3.6 B2 3.4 4.2 6.4 6.2 4 4.6 3.01 4.7 B3 4.4 3.6 6.2 6 4.1 4.6 4.12 4.15 B4 3.1 3.4 6.4 6 4.3 4.7 4.11 3.9 B5 3.9 3.8 6.1 6 4 4.7 3.8 3.6 C1 2.6 3.5 6 6 4 4.8 4 4 C2 3.6 4.7 6.2 6.1 4.1 4.7 4.21 4.08 C3 4 4.6 6.3 6 4.2 4.2 3.97 4.09 C4 4.1 3.1 6 6.1 4.4 4.7 2.98 4.1 C5 5.1 4.6 6.2 6.1 4.2 4.6 4.1 4.15 D1 4.5 3.9 6.3 6.1 4.1 4.6 3.58 4.2 D2 4.3 3.8 6.2 6.2 4 4.7 3.88 3.67 D3 4.3 4.5 6.2 6.3 4.1 4.7 4.1 4 D4 4.3 5.9 6.2 6.2 4 4.5 3.9 3.9 D5 4.6 4.5 6.1 6.9 4.1 4.6 3.68 4.11 E1 3.5 5.5 6.3 6.1 4.2 4.6 2.99 4.21 E2 4 4.7 6.2 6.2 5.2 4.7 3.27 4.51 E3 5 6.2 6.1 6.1 4.1 4.8 3.52 3.96 E4 4.2 4.1 6.1 6.1 4.2 4.9 4 4.28 E5 2.9 4.1 6.1 6.1 4.2 4.9 3.91 4.28

87

Sample Mg Test1 Mg Test2 K Test1 K Test2 Na Test1 Na Test2 Sum Base Test1 Sum Base Test2

MG1 MG2 K1 K2 NA1 NA2 SUMBASE1 SUMBASE2 A1 0.93 0.41 0.2 0.56 0.05 0.11 4.06 5.94 A2 1.01 0.44 0.18 0.42 0.07 0.09 5.45 5.15 A3 0.91 0.53 0.17 0.71 0.05 0.16 5.43 5.15 A4 0.84 0.4 0.18 0.84 0.07 0.13 5.05 4.94 A5 0.64 0.39 0.16 0.62 0.04 0.13 5.2 5.14 B1 0.7 0.4 0.18 0.46 0.05 0.09 5.52 5.03 B2 0.8 0.57 0.19 0.5 0.08 0.1 5.24 5.05 B3 1.08 0.49 0.2 0.88 0.07 0.13 5.2 5.38 B4 1.1 0.38 0.21 0.51 0.09 0.11 5.39 6.16 B5 1 0.37 0.2 0.97 0.1 0.2 5.2 6.3 C1 1 0.39 0.18 0.58 0.01 0.11 4.63 5.09 C2 1.08 0.4 0.17 0.66 0.05 0.13 3.62 4.96 C3 1 0.36 0.15 0.81 0.07 0.15 4.02 4.96 C4 0.84 0.29 0.1 0.7 0.03 0.15 3.95 5.24 C5 0.92 0.31 0.1 0.74 0.04 0.13 5.16 5.33 D1 0.7 0.37 0.13 0.4 0.05 0.08 4.46 5.05 D2 0.84 0.28 0.15 0.57 0.06 0.11 4.93 4.63 D3 1 0.25 0.23 0.91 0.1 0.17 5.43 5.32 D4 1 0.4 0.21 0.66 0.07 0.13 5.18 5.09 D5 0.72 0.37 0.18 0.83 0.07 0.14 4.65 5.45 E1 0.68 0.38 0.14 0.76 0.06 0.13 3.87 5.48 E2 0.7 0.39 0.13 0.65 0.05 0.11 4.15 5.66 E3 0.8 0.4 0.12 0.87 0.06 0.15 4.5 5.38 E4 1.01 0.41 0.15 1 0.05 0.17 5.21 5.86 E5 0.99 0.41 0.16 1 0.04 0.17 5.1 5.86

88

Sample CEC Test1 CEC Test2 Base Sat Test1 Base Sat Test2 Available P

Test1 Available P

Test2 CEC1 CEC2 BASESAT1 BASESAT2 PHOSPH1 PHOSPH2

A1 20.6 33 20 18 5.9 6.5 A2 23.8 20.6 23 25 8.5 7.6 A3 25.6 21.7 21 24 5.9 10.5 A4 22.3 29.7 23 17 7.9 8.3 A5 28.1 28.8 19 18 6.1 9 B1 24.1 22.9 23 22 3.3 4.5 B2 27.3 28.9 19 17 3.3 3.9 B3 28.9 23.4 18 23 5.6 8.4 B4 24.1 23.5 22 26 9.5 6.2 B5 30.6 21.8 17 29 6.3 22 C1 26.9 25 17 20 6.9 4.8 C2 29.3 13.7 12 36 4.7 9.2 C3 29.4 12.2 14 41 10 9.3 C4 33.2 11.6 12 45 7.9 5.6 C5 25.8 22.3 20 24 7.5 8.8 D1 28.4 25.8 16 20 7 5.9 D2 19.6 29.7 25 16 3.2 5.9 D3 24 16.9 23 31 7.3 9 D4 32.6 16.9 16 30 8.9 6.6 D5 21.4 23.4 22 23 5.1 10.9 E1 22.5 26.3 17 21 8.3 9.3 E2 24.4 24.3 17 23 5.5 5.6 E3 31.8 26.1 14 21 8.7 18.6 E4 29.5 23.3 18 25 7 11.3 E5 29 23.3 18 25 5.8 11.3

89

Sample Acidity Test1 Acidity Test2 ECEC Test1 ECEC Test2

ACIDITY1 ACIDITY2 ECEC1 ECEC2 A1 2.29 0 6.35 5.94 A2 1.14 0.6 6.59 5.75 A3 1.16 0.61 6.59 5.76 A4 1.14 1.21 6.19 6.15 A5 1.54 0.6 6.74 5.74 B1 0.57 1.17 6.09 6.2 B2 0.58 0.58 5.82 5.63 B3 1.15 1.15 6.35 6.53 B4 1.15 1.2 6.54 7.36 B5 2.31 0.6 7.51 6.9 C1 2.33 0.6 6.96 5.69 C2 2.28 1.19 5.9 6.15 C3 0 0.58 4.02 5.54 C4 1.15 1.17 5.1 6.41 C5 2.29 0.61 7.45 5.94 D1 1.72 1.32 6.18 6.37 D2 1.74 1.17 6.67 5.8 D3 1.17 0.58 6.6 5.9 D4 1.15 0.61 6.33 5.7 D5 2.31 0.63 6.96 6.08 E1 1.16 1.78 5.03 7.26 E2 0 1.2 4.15 6.86 E3 1.16 0.6 5.66 5.98 E4 1.16 1.2 6.37 7.06 E5 1.14 1.2 6.24 7.06